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Bimolecular Coupling Reactions through Oxidatively Generated Aromatic Cations: Scope and Stereocontrol.

ABSTRACT: Chromenes, isochromenes, and benzoxathioles react with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone to form stable aromatic cations that react with a range of nucleophiles. These oxidative fragment coupling reactions provide rapid access to structurally diverse heterocycles. Conducting the reactions in the presence of a chiral Brønsted acid results in the formation of an asymmetric ion pair that can provide enantiomerically enriched products in a rare example of a stereoselective process resulting from the generation of a chiral electrophile through oxidative carbon-hydrogen bond cleavage.

SUBMITTER: Cui Y

PROVIDER: S-EPMC3728896 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Bimolecular Coupling Reactions through Oxidatively Generated Aromatic Cations: Scope and Stereocontrol.

Cui Yubo Y Villafane Louis A LA Clausen Dane J DJ Floreancig Paul E PE

Tetrahedron 20130901 36

Chromenes, isochromenes, and benzoxathioles react with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone to form stable aromatic cations that react with a range of nucleophiles. These oxidative fragment coupling reactions provide rapid access to structurally diverse heterocycles. Conducting the reactions in the presence of a chiral Brønsted acid results in the formation of an asymmetric ion pair that can provide enantiomerically enriched products in a rare example of a stereoselective process resulting ...[more]

PMID: 23913987

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